1. Field of Invention
This invention relates to improvements in book marks and other devices distinguished by numerical or symbol differences and, more particularly, to an improved book marking unit for the pages of a book.
2. DESCRIPTION OF PRIOR ART
Numerous type of bookmarks have been used in the past to indicate the last page of a book which has been read when the reading of the book is to be divided into periods. For the most part, bookmarks are made of a single sheet of cardboard or heavy duty paper for insertion into the book at the location of the last portion to be read. Other techniques for marking a book have been to dog-ear a page by folding it over at the upper corner thereof to indicate the last page of reading by the reader.
While book marks of conventional design are adequate for most purposes, improvements are desirable in this field for one or more reasons. For instance, paper or cardboard bookmarks have a tendency to fall out of the book and the last place where reading stops is lost. Moreover, it is not desired to cause dog-ears to be formed on pages of the book especially if the book is to be saved over a long period of time in a clean condition. Because of these drawbacks, a need exists for improvements in indicating devices which are suitable for use as bookmarks and other such symbol indicating means. The present invention satisfies this need.